Multimesh models / changing meshes between them

I have to simple multimesh models just to play around changing meshes between them. Both created in 3Ds max, both have same bone structure and mesh parts (head, body, hands, legs). Those parts attached to same bones in both models. You can check them here (can't attach them to this question): http://yakov.dls.net/~rcr/fbx/ I rig them both in Unity after fbx import. Only right palm bone is left unbound after autorig, but it easily corrected manually. I place both models on the scene. When I try to switch bodies and heads - everything is fine. When I'm trying to switch legs or hands meshes appear distorted. What am I missing with hands and legs? Any help and suggestions would be appreciated.